1. Field of the Invention
This invention relates to a method and apparatus for generating power from vehicle and pedestrian traffic. More particularly, the invention relates to a method and apparatus for utilizing the weight of moving highway and railway traffic to compress fluid and for recovering energy from fluid so compressed.
2. Description of the Relevant Art
The relevant art is described hereinbelow.
U.S. Pat. No. 4,238,687, issued in 1980 to Martinez, entitled "HIGHWAY TURBINE", discloses an apparatus for generating power and mounted in a roadbed. The apparatus includes rocker plates connected by linkages to one or more turbine wheels, and a generator which is operated by the turbine wheels via a common shaft. As a vehicle passes over the apparatus, the rocker plates are forced to move in a substantially vertical direction, thus rotating the turbine wheels and causing the generation of electricity.
U.S. Pat. No. 4,409,489, issued in 1983 to Hayes, entitled "ROAD TRAFFIC ACTUATED GENERATOR", discloses an apparatus for generating power including a network of resilient, fluid-containing tubes laid over a roadway and attached to a turbine generating system. As a vehicle passes over the tubes, the working fluid is pumped through the tubes and into the turbines, thereby causing the generation of electricity.
U.S. Pat. No. 4,434,374, issued in 1984 to Lundgren, entitled "DEVICE FOR GENERATING ELECTRICITY BY PEDESTRIAN AND VEHICULAR TRAFFIC", discloses an apparatus for generating electricity which is comprised of a roadway or a sidewalk tread plate capable of substantially vertical motion, a series of rocker arms communicating with a common shaft, and a generator operated by the common shaft. As pedestrian or vehicular traffic overpasses the tread plate, its consequent downward motion depresses the rocker arms, which in turn rotate the common shaft, thereby generating electricity.
Japanese Patent No. 52-8411, issued in 1977 to Kanji Sato, entitled "RUNNING ROAD POWER GENERATING STARTING DEVICE", discloses an apparatus for generating electricity. The apparatus includes: a series of treadle plates capable of substantially vertical motion; vertical shafts fitted with gear teeth; gears communicating with the gear teeth; a power generator; and shafts connecting the gears with the generator. As a vehicle passes over the treadle plates, the vertical shafts move downwardly, causing the gear to turn and thereby rotating the connecting shafts to operate the generator.
These relevant art devices are deficient in certain respects. Their designs are inefficient in that, in each case, only the downward force of the weight of a vehicle on a treadle or fluid tube is recovered. Accordingly, their placement on the roadway, to be efficient, must of necessity be unnecessarily intrusive to the overflow of vehicle traffic. This intrusion causes an unsteady ride and results in the discomfort of passengers.
For a more specific example of the deficiencies inherent in the relevant art devices, the network of collapsible bodies disclosed by Hayes pressurize a working fluid when a vehicle overpasses the collapsible bodies. Besides embodying the disadvantages discussed above, this design discloses a temporary, flexible device which is exposed entirely to the elements and to the direct overpass of highway vehicles of varying shapes and weights, thus subjecting it to considerable strain and excess fatigue. The Hayes apparatus is further incapable of application to transport systems which are of considerably greater mass, such as vehicles which operate on rail systems.
The present invention effectively overcomes the deficiencies attendant the known art.